Method of rolling strip

Abstract

In a method of rolling a strip between work rolls with small and large diameters, while tensioning and bending the strip, the diameter ratio of the small and large work rolls is chosen from the range of 1/1.5 to 1/10, at least one of the work rolls or of rolls in a group backing up the work rolls is driven, and the strip is rolled as it is forced through the work rolls while being bent toward or around either the small or large work roll at a strip entry-exit angle between 5° and 30°.

We claim: 
     
       1. A method of rolling a strip between two work rolls with small and large diameters respectively, for producing a relatively large amount of plastic deformation in the strip to substantially reduce the width of the strip, while tensioning and bending the strip, comprising: choosing the diameter ratio of said small and large work rolls to be in the range of 1/7 to 1/10; driving at least one of said work rolls or at least one roll in a group backing up said work rolls; rolling the strip as it is forced through said work rolls while bending the strip toward or away from either said small or large work roll at a strip entry-exit angle between 20° and 30°; and applying a pressure onto the strip using said rolls to squeeze the strip;   the pressure being sufficient to substantially plastically deform the strip by an amount which would require 25% to 50% more pressure if the entry-exit angle were zero and the small and large rolls were of equal diameter.   
     
     
       2. A method according to claim 1, wherein the strip is rolled in a single nip between said small and large rolls, a plurality of said small and large rolls provided for receiving said strip in series, each small and large roll defining only a single nip therebetween and a single nip in total defined by each of said small and large rolls.